If the chicken broth has been frozen for the 14 days then yes you can use the frozen chicken broth after 14 days.
However if the chicken broth has been only refrigerated and has been refrigerated for 14 days then it's likely bad and should be thrown out.
Chicken broth lasts for around 4 to 5 days in the refrigerator before it goes bad and gets sour and grows bacteria.
If your chicken broth has actually gone bad then it will smell sour or have a bad taste to it.
But if the chicken broth has been in the refrigerator for 14 days then it's very likely that it's 100 percent bad either way.
I would not eat any chicken broth that has been in the refrigerator for 14 days.
But if the chicken broth has been frozen for those 14 days then it would still be good and safe to eat or drink.